Apparatus for making absorbent pads

ABSTRACT

Improvement in apparatus and method for producing disposable absorbent pads, such as diapers, comprising applying pressure-sensitive strips of adhesive tape to the diapers by means of apparatus which includes conveyor belt for advancing diapers, the conveyor belt being narrower than the diapers thus allowing the side edges of the diapers to extend beyond the conveyor belt; reel of adhesive tape ribbon disposed at each side and below the conveyor belt; rotatable drum, provided with suction valves, positioned below the overlapping side edges of the diapers, means for advancing the ribbon against the drum whereby the ribbon is held against the drum by the suction valves, rotatable cutting means for severing the ribbon into strips of adhesive tape while the ribbon is held against the drum, situated at each side and below the conveyor belt; and rotatable pressure roll, disposed directly above the rotatable drum, for affixing the strip of adhesive tape to the overlapping edges of the diapers in cooperation with the rotatable drum.

June 27, 1972 A. B. EREKSON 3,673,019

APIU JM'JI'US FOR MAKING ABSORBENT PADS Filed Nov. 20, 1969 2 Sheets-Sheet l June 27, 1972 A. B. E REKSON 3,673,019 I APPARATUS FOR MAKING ABSORBENT PADS Sheets-Sheet 2 Filed Nov. 20, 1969 i: L: I.

FIG.2

United States Patent 3,673,019 APPARATUS FOR MAKING ABSORBENT PADS Arthur B. Erekson, Scarsdale, N.Y., assignor to Borden, Inc., New York, N.Y. Filed Nov. 20, 1969, Ser. No. 878,390

Int. Cl. A41h 37/00 US. Cl. 156-66 9 Claims ABSTRACT OF THE DISCLOSURE Improvement in apparatus and method for producing disposable absorbent pads, such as diapers, comprising applying pressure-sensitive strips of adhesive tape to the diapers by means of apparatus which includes conveyor belt for advancing diapers, the conveyor belt being narrower than the diapers thus allowing the side edges of the diapers to extend beyond the conveyor belt; reel of adhesive tape ribbon disposed at each side and below the conveyor belt; rotatable drum, provided with suction valves, positioned below the overlapping side edges of the diapers, means for advancing the ribbon against the drum whereby the ribbon is held against the drum by the suction valves, rotatable cutting means for severing the ribbon into strips of adhesive tape while the ribbon is held against the drum, situated at each side and below the conveyor belt; and rotatable pressure roll, disposed directly above the rotatable drum, for affixing the strip of adhesive tape to the overlapping edges of the diapers in cooperation with the rotatable drum.

The present invention relates to the method and apparatus for making disposable absorbent pads. Although the present invention may be employed in the manufacture of various forms of disposable absorbent pads such as diapers, incontinent pads, antiseptic bandages, it is particularly suitable for use in the manufacture of the disposable diapers.

A number of attempts have been made to continuously manufacture disposable diapers having affixed thereto a pair of adhesive strips of tape for securing the diaper edges around the waist of a child and thus eliminate the necessity for buttons, tabs, pins, etc. These attempts have been unsuccessful for the simple reason that no apparatus was available for applying the tape strips to the diapers in a quick, inexpensive and efficient manner.

It is, therefore, an object of this invention to provide a method and apparatus for continuously manufacturing diapers provided with adhesive tape strips.

Another object of the invention is to provide method and apparatus for manufacturing disposable diapers which can be quickly and easily secured to the baby without the use of pins, buttons, metal fasteners, or the like, or the necessity of wetting anadhesive surface, and with little disturbance to the child.

A further object of the invention is the provision of a method and apparatus for producing disposable absorbent pads in an economical and an efficient manner.

The method and apparatus will now be described in conjunction with the attached drawings wherein:

FIG. 1 is a side view of the apparatus showing manufacture of the diapers and aflixation of the adhesive tape strips;

FIG. 2 is a top view of a diaper showing the adhesive tape strips and the sealing lines imparted by the corresponding rolls;

FIG. 3 is a cross-sectional view of one variant of an adhesive tape strip which is secured to the opposite edges of the diaper by a pair of cooperating rolls.

Patented June 27, 1972 "ice FIG. 4 is a top view showing structural arrangement of a conveyor belt, a diaper and vacuum drums;

FIG. 5 is a modification of the apparatus depicted in FIG. 1 relating to affixation of the adhesive tape strips to diapers;

FIG. 6 is another embodiment of the apparatus for aflixing adhesive tape strips to diapers.

Referring to FIG. 1, a ribbon of absorbent shredded pulp 1, or a material of similar characteristics, is moved axially between a pair of conventional roller cutters 10, 11 whereby it is severed into separate pad sections 2. A reel of plastic film 15, such as polyethylene, is mounted for rotation below conveyor belt 12 and a reel of paper 17 is mounted above conveyor belt 12. Conveyor belt 12 is draped over rolls 13 and functions to continuously move the diaper ribbon assembly. The pad sections are aligned with a mouth formed by plastic film 15 running over the conveyor belt 12 and the continuous sheet of paper 17 extending over guide roller 16 and :under holddown roll 14. The pad sections are forced into the mouth created by plastic film 15 and paper 17 whereby it is enveloped in plastic -film on the underside and paper on the upper surface.

Dimensionally, the pad sections, which are centered between paper and film, are of a lesser width than the film or paper and are generally substantially less than the width thereof, while the film and paper are of equal width. Specifically, the paper is somewhat wider than the film. to accommodate the thickness of the pad.

The three-layer diaper ribbon assembly of plastic film, absorbent shredded pulp pad and paper is advanced linearly along conveyor belt 12 and under hold-down roll 14. Roll 14 is of a conventional type-being centrally indented but otherwise provided with a smooth outer surface serving to apply pressure and thus to compact or compress the diaper ribbon assemly and to form the paper over the pad. The three-layer diaper ribbon assembly is then further moved past rolls 39 and 18 where it is subare provided to contain the pad sections and prevent them from shifting, while the outer sealing lines are made in order to heat-seal the edges of plastic film and paper.

Roll 18 has four protruding heated bars on its surface disposed transversely with respect to the longitudinal axis of conveyor belt 12. These bars have blunt edges and function to cause fusion of plastic film and paper on contact to define the transverse sealing lines.

The affixation of the narrow-width adhesive strips 42, as shown in FIG. 3, having removable liner 44, tfihe longitudinal edges of each diaper 21 is effected by roller 23 having diametrically opposed vacuum valves 24 and 25 on its circumferential face. As is evident from FIG. 4, side edges of diaper 21 overlap belt conveyor 19. Rollers 23 are positioned below the overlapping edges of the diaper with a portion of their surface underlying the overlapping edges of the diaper in order to secure a strip of the adhesive tape to the underside of the overlapping edges of the diaper in conjunction with cooperating pressure rolls 2. Adhesive tape strips 42 are strips of conventional adhesive tape with the removable liner completely removed from the portion of the strip which is secured to the diaper. The removable liner 44 is folded on itself to provide a tab for stripping it from the strip of adhesive tape. These adhesive tape strips are used by the baby attendant to secure the diaper about infants waist.

A reel of pressure-sensitive tape 26 is mounted for rotation on shaft 27. The tape, with one-half of the sticky side exposed and facing downwardly, is advanced in the interface 31 defined by metering belts 29, entrained over rollers 32, 33 and 34, 35. Identical arrangement is provided on the opposite side of the conveyor belt 19. Roll 36, which is provided with diametrically-opposed cutting blades 37, is disposed in parallel relationhip to roll 23 and severs the tape ribbon intermittently as it is extended by belts 29, 30 against roll 23. To avoid fouling of the belts with adhesive tape, liner 44, one half of it being folded on itself, is provided on a portion of the adhesive tape strip 42 leaving a strip of the sticky face 48 thereof exposed, as plainly illustrated in FIG. 3. Rollers 32, 33, and 34, 35 are of a smaller axial extent than roll 23 and are off-set therefrom to allow belts 29 and 30 to come in contact only with the folded removable liner 44 and not With the sticky exposed face 48 of the strip of adhesive tape.

In operation, rotation of roll 23 is in timed relation to the linear movement of belt 19 and synchronized with rotation of roll 36. Ribbon of adhesive tape 26 is fed to measuring belts 29 and 30, which present the tape ribbon to roll 36 for sequential severing into strips of predetermined width.

As roll 36 rotates, blades 37 severe the ribbon of adhesive tape 26 into narrow strips 42. Each of the tape strips 42 is drawn against either of the vacuum valves 24 or 25 and the sticky portion thereof is presented against underside of the overlapping portion of diaper 21. Tape strip 42 is atfixed to the underside of the overlapping portion of the diaper by means of pressure created by cooperating rolls 22 and 23. The liner may be easily removed by the baby attendant by simply pulling on the folded strip of removable liner 44. Identical components provided on the opposite side of conveyor belt 19 operate in identical fashion to aflix another tape strip 42 to the opposite side of diaper 21.

The apparatus, and modifications thereof, described herein is adaptable to continuous or intermittent operation. If the apparatus were to be operated intermittently, then additional components such as timing devices and breaking means, would have to be installed.

In a modification illustrated in FIG. 5, a reel of adhesive tape .26 is provided without any removable liner at all. As shown in FIG. 5, the adhesive tape is advanced between cooperating measuring belts 29, 30, with its sticky side facing downwardly. To prevent fouling of the belts with the adhesive tape, removable liner 38 is brought against the sticky side of adhesive tape 26 in order to cover the portion of the adhesive tape which comes into contact with the measuring belts 29, 30. Subsequent operations are identical to the embodiment described above. In this manner, a strip of adhesive tape, with a removable liner, can be applied .at opposite edges and at the upper portions of a diaper.

Another embodiment of the method and apparatus for applying strips of adhesive tape to diapers, and absorbing pads in general, is shown in FIG. 6. A reel of adhesive tape is disposed below belt conveyor 19. This tape may be provided with or without removable liner 52. If adhesive tape 50 is provided with liner 52, the liner is strippedoif by passing the tape through metering rolls 53 and winding the liner on reel 54. A narrow strip 55 of tape 50 is then severed by blade 56 mounted on a rotatable cylinder 57 and picked-up by vacuum drum 58. The vacuum drum affixes a portion of the strip 55 to the underside of the overlapping edge of diaper 21, with a portion of the sticky face of strip 55 remaining exposed. As in previously described embodiments, the exposed sticky face of tape 50 is provided with a removable liner. This operation is accomplished by positioning a reel of the removable liner ribbon 60 above the conveyor belt 19 and advancing it against blade 62 mounted on rotatable cylinder 64. A strip of liner ribbon 60 is cut by blade 62 and picked up by vacuum drum 66 which applies the strip to the exposed sticky portion of adhesive tape strip 55. Removable liner 60 may be ordinary backing paper, one half of which may be folded on itself, as is liner 44 shown in FIG. 3.

Any number of adhesive strips may be applied to an absorbent pad, depending on the type of adsorbent pad that is being manufactured. Although four adhesive strips are shown in FIG. 2, it should be understood that a diaper requires only two at one end.

For the sake of illustration, the apparatus herein described may be designed to manufacture adult incontinent pads at the rate of per minute, and diaper pads at the rate of per minute. The incontinent pad may have overall dimensions'of 25" x 35" with a centrally located cellulose wadding have dimensions of 5" x 26". With respect to the diaper pad, the overall dimensions are 12 /2" x 17", with the centrally disposed absorbent pad measuring 5 /2" x 13".

After application of the adhesive strips to the diaper ribbon assembly, or any other disposable pad, the diaper ribbon assembly is advanced to another station where the ribbon is severed into individual diapers which are stacked and packaged.

What is claimed:

1. Apparatus for applying strips of pressure-sensitive adhesive tape to diapers comprising conveyor means for advancing the diapers, said conveyor means being narrower than the diapers thus permitting side edges of the diapers to overlap the conveyor means; rotatable suction means for transferring the strips of adhesive tape into position for aflixation to the side edges of the diapers disposed directly below each of the overlapping side edges of the advancing diapers; a rotatable means positioned above the overlapping side edges of the diapers and cooperating with said rotatable suction means to aflix said strips to the diapers; means for feeding adhesive tape ribbon to said rotatable suction means situated at each side of the conveyor means; and cutting means for severing the adhesive tape ribbon into adhesive tape strips positioned in operative relationship with said rotatable suction means at each side and below said conveyor.

2. Apparatus of claim 1, wherein said means for feeding adhesive tape ribbon is a pair of measuring conveyor belts forming an interface through which the adhesive tape ribbon is passed on its way to said cutting means.

3. Apparatus of claim 2 including means in conjunction with said pair of measuring conveyor belts for applying a removable'liner to a portion of the sticky surface of the adhesive tape ribbon prior to advancement of said ribbon through the interface formed by the said pair of measuring conveyor belts.

4. Apparatus for applying strips of pressure-sensitive adhesive tape ribbon to diapers comprising conveyor means for advancing the diapers, said conveyor means being narrower than the diapers thus permitting side edges of the diapers to overlap said conveyor means; first rotatable suction means for transferring the strips of adhesive tape into position for atfixation to the diapers disposed directly below each of the overlapping side edges of the advancing diapers; means for advancing the tape ribbon, having an exposed sticky side, against said first rotatable suction means with the non-sticky side thereagainst; cutting means for severing the adhesive tape ribbon into adhesive tape strips positioned in operative relationship with said first rotatable suction means; means for advancing removable liner ribbon; cutting means for severing the liner ribbon into liner strips; and second rotatable suction means for grasping and transferring said liner strips to a position over the exposed sticky surface of said adhesive tape strips, said second rotatable suction means being disposed directly over said first rotatable suction means and cooperating therewith to afilX Said adhesive tape strips.

5. Apparatus of claim 4, wherein the adhesive tape ribbon is provided with a liner, said apparatus including means for stripping said liner from the adhesive tape ribbon prior to advancement of the ribbon to said cutting means.

6. Apparatus for applying strips of pressure-sensitive adhesive tape to absorbent pads comprising conveyor means for advancing the absorbent pads, said conveyor means being narrower than the absorbent pads thus permitting side edges of the absorbent pads to overlap the conveyor means; rotatable suction means for transferring the strips of adhesive tape into position for aflixation to the side edges of the absorbent pads; a rotatable means positioned in cooperating relation with said rotatable sucnon means for afiixing said strips to the side edges of the absorbent pads; and means for feeding the strips of adhesive tape ribbon to said rotatable suction means.

7. Apparatus of claim 6 wherein said rotatable suction means is a suction roll and sad rotatable means is a pressure roll, said suction roll is disposd just beyond the edge of said conveyor and below it so that it underlies the overlapping edges of the advancing absorbent pads, and said pressure roll is disposed above said conveyor means and just beyond its side edge in a position directly above but spaced from said suction roll to permit tight passage of the absorbent pads between said suction roll and said pressure roll whereby the strips of adhesive tape ribbon are aflixed to the side edges of the absorbent pads.

8. Apparatus of claim 7 wherein a pair of said suction and pressure rolls are mounted on both sides of said conveyor means; and the absorbent pads are diapers.

9. Apparatus of claim 8 including the cutting means for severing the adhesive tape ribbon into adhesive tape strips positioned in operative relationship with said r0- tatable suction means at each side and below said conveyor.

References Cited UNITED STATES PATENTS 2,627,858 2/1953 Miller 128287 3,352,733 11/1967 Kruce 156-552 3,416,414 12/1968 Smithe 156521 BENJAMIN A. BORCHELT, Primary Examiner H. I. TUDOR, Assistant Examiner US. Cl. X.R. 156377, 521, 552 

